Shop by Brand Yamaha OutboardPiston/Piston Kit ; Piston Pin ; Piston Ring Back Piston Kit 6H4-11631-01 STD Viewer:458 OEM No. : 6H4-11631-01-STD For YAMAHA Outboard 40, 50 HP You May Also Be Interested In Piston Kit 662-11631-01 STD Piston Ring 6H4-11601-00-00 STD Needle Valve 6E0-14392-00-00 Insert Cartridge 61A-44322-02-00